Most instant messaging programs by default transmit clear text, which means that an attacker that has succeeded in intercepting the communications will be able to follow the conversation. If the text is encrypted, an attacker would not be able to read it. OTF also regularly changes its encryption keys so that if one key is compromised, multiple conversations can't be decoded. It also does not assign a digital signature to conversations, meaning that a person could argue that a captured conversation was not theirs or tampered with.

OTR is an easy-to-use tool can be used to authenticate another person a user is chatting with as well as encrypt the communication. This is especially important for people who feel they may be the target of electronic surveillance, such as anyone in China.

But "there is little value in having a nicely-conceived encryption tool if the implementations that people actually use are filled with security bugs," wrote Dan Auerbach and Chris Palmer of the EFF. "Therefore, we decided to do an audit to find and fix some of those bugs."

The EFF researchers found errors in "libpurple" messaging client library which is used by both Adium and Pidgin.

"We found and fixed quite a few bugs, which you might be able to see now and in the coming weeks and months by looking for security updates within the various code bases," they wrote. "Given the crucial role played by this software as a platform for OTR and other encrypted messaging solutions, we hope that it will get the security attention that it deserves and continue to be reviewed regularly by the developers actively working on the projects as well as the community of users with an interest in encrypted communication."